Software Defined Radio (SDR) and Cognitive Radio (CR) are fast technologies, which can be used to reduce the spectrum shortage problem. The modern software defined radio has been called the heart of a cognitive radio. The applications executing on the radio differentiate a cognitive radio from a software-defined radio. Additional hardware in the form of sensors and actuators increases the more ...

While bringing the potential for solving the spectrum underutilization problem using methods such as dynamic and opportunistic spectrum access, Cognitive Radios (CRs) also bring a set of security issues and potential breaches that have to be addressed. These issues come out mainly from the two important capabilities implemented within CRs: their cognition ability and reconfigurability. This cha...

Ad hoc network is a collection of wireless mobile nodes that dynamically form a temporary network without the use of any existing network infrastructure or centralized administration. A cognitive radio is a radio that can change its transmitter parameters based on interaction with the environment in which it operates. The basic idea of cognitive radio networks is that the unlicensed devices (co...

Ad hoc network is a collection of wireless mobile nodes that dynamically form a temporary network without the use of any existing network infrastructure or centralized administration. A cognitive radio is a radio that can change its transmitter parameters based on interaction with the environment in which it operates. The basic idea of cognitive radio networks is that the unlicensed devices (co...

Large parts of the assigned spectrum is underutilized while the increasing number of wireless multimedia applications leads to spectrum scarcity. Cognitive Radio is an option to utilize non-used parts of the spectrum that actually are assigned to primary services. The benefits of Cognitive Radio are clear when used in emergency situations. Current emergency services rely much on the public netw...

Cognitive Radio provides enhanced wireless communication performance through context-aware sensing and adaptation. Cooperative relay enhances network connection quality and improved system throughput. Applying cooperative relay communication technique on Cognitive Radio networks enables Cognitive Radio to opportunistically exploit cooperation between network nodes. This integrated design that b...

The current trends in vehicular adhoc networks are bringing a variety of changes to the existing one. The primary focuses in the area of vehicular adhoc networks are connectivity and file distribution which is broadcast by roadside units to the onboard units during handoffs. The connectivity of vehicular adhoc network can be improved by the use of cognitive radio networks with interference mana...

To encounter the emergent necessity of radio spectrum, which is a limited natural resource, proper utilization of the radio spectrum is a must. Introduction of cognitive radio networks can play a vital role to solve the spectrum scarcity. Cognitive radio uses an open spectrum allocation technique to make more efficient utilization of the wireless radio spectrum and reduce the bottleneck on the ...